Acceptable Quality Level (AQL) Table





Table A is divided into two parts, General inspection Level and Special Inspection Level. The inspection level determines the relation between the batch size and sample size. Levels I, II, and III are general inspection levels:

• Level II is designated as normal.
• Level I requires about half the amount of inspection as level II, and is used when reduced sampling cost are required and a lower level of discrimination (or power) can be tolerated.
• Level III requires about twice the amount of inspection as level II, and is used when more discrimination (or power) is needed.
   

How do I determine the right sample size and acceptance number for my inspection:

For example, there are 4,000 units going for inspection, according to our default AQL standard that General inspection Level II , acceptable quality level for major defects is 2.5, for minor defects is 4, and the number for critical defects is 0., table A indicates that sample size code letter should be “L” if lot size is 4,000 units. And table B indicated that the sample size of “L” should be 200 units, that means the corresponding acceptance number for minor defects is 14, for major defects is 10, and for critical defects is 0.

Remark:
The sampling table is based on a homogenous lot of products, and is assumed that the batch is manufactured on one single production location. If the batch consists of products originated from multiple production locations, this will influence the homogenous quality of the sample selected for inspection.
It is important to understand that acceptance sampling cannot imply 100% error free products. Continuous process improvement by the factory is the way to achieve 100% error free products.

Our suggestion on AQL levels:
 

If you are interested in or have any query, please don't be hesitant to contact with us by kentelservice@gmail.com.